Co-supplementation of single and multi doses of vitamins C and E ameliorates cisplatin-induced acute renal failure in mice

Higher doses of antioxidant vitamins C and E have been proved to be effective against cisplatin-induced nephrotoxicity in animals. However, the possible effective equivalent dose in human was found to be higher than that of the upper tolerable intake level (UL) for these vitamins. Hence, the current study was aimed to evaluate the protective effect of co-supplementation of single and multi doses of vitamins C and E against cisplatin-induced acute renal failure in mice. Single dose of vitamin C (500 mg/kg), vitamin E (500 mg/kg), and vitamin C plus vitamin E (250 mg/kg each) were administered orally 1 h prior to cisplatin (12 mg/kg, i.p) injection, whereas in a multidose study they were administered 1 h prior, and 24 and 48 h after the cisplatin injection. Serum urea and creatinine levels were estimated 72 h after the injection of cisplatin. Renal concentrations of glutathione (GSH) and malondialdehyde (MDA) were also determined. Co-supplementation of vitamins significantly protected the cisplatin-induced increased levels of serum urea, creatinine, renal MDA, and the declined renal GSH level. Administration of single and multi doses of vitamin C plus E (250 mg/kg each) rendered significant nephroprotection. Therefore, accounting for the rare side effect from high intake of vitamins C and E observation of this study indicates that a multidose combination therapy of these vitamins at their lower doses can be effective in protecting the cisplatin-induced renal damage. The protection is partially mediated through the antioxidant effect of the vitamins.     

Are we estimating the adverse effects of shock-wave lithotripsy on a faulty scale?

The adverse effect of shock-wave lithotripsy (SWL) for renal stones on blood pressure is currently defined as its post-treatment increase. On the contrary, we hypothesize that even mild, unilateral renal obstruction initiates an increase in blood pressure. Then, in absence of treatment-induced injury, the stone removal should decrease the blood pressure. We derived the formula to assess the expected change in the mean arterial pressure following relief of renal obstruction without affecting the kidney functions. The predictions were well replicated in the cohort of patients with renal stone treated with parenchyma-saving open surgery, with 6.4 mmHg decrease at 3 months. On the contrary, in SWL cohort, instead of the expected 4.7 mmHg decrease, the blood pressure was unchanged. In conclusion, the absence of decrease in blood pressure is a very common adverse effect of SWL, leading to an epidemiologically significant increase in the risk of arterial vascular events.     

Data visualization speeds review of potential adverse drug events in patients on multiple medications

Patients on multiple medications are at increased risk for adverse drug events. While physicians can reduce this risk by regularly reviewing the side-effect profiles of their patients’ medications, this process can be time-consuming. We created a decision support system designed to expedite reviewing potential adverse reactions through information visualization. The system includes a database containing 16,340 unique drug and side-effect pairs, representing 250 common medications. A numeric score is assigned to each pair reflecting the strength of association between drug and effect. Based on these scores, the system generates graphical adverse reaction maps for any user-selected combination of drugs. A study comparing speed and accuracy of retrieving side-effect data using this tool versus UpToDate® demonstrated a 60% reduction in time to complete a query (61 s vs. 155 s, p < 0.0001) with no decrease in accuracy. These findings suggest that information visualization can significantly expedite review of potential adverse drug events.     

An in situ forming biodegradable hydrogel-based embolic agent for interventional therapies

We present here the characteristics of an in situ forming hydrogel prepared from carboxymethyl chitosan and oxidized carboxymethyl cellulose for interventional therapies. Gelation, owing to the formation of Schiff bases, occurred both with and without the presence of a radiographic contrast agent. The hydrogel exhibited a highly porous internal structure (pore diameter 17 ± 4 μm), no cytotoxicity to human umbilical vein endothelial cells, hemocompatibility with human blood, and degradability in lysozyme solutions. Drug release from hydrogels loaded with a sclerosant, tetracycline, was measured at pH 7.4, 6 and 2 at 37 °C. The results showed that tetracycline was more stable under acidic conditions, with a lower release rate observed at pH 6. An anticancer drug, doxorubicin, was loaded into the hydrogel and a cumulative release of 30% was observed over 78 h in phosphate-buffered saline at 37 °C. Injection of the hydrogel precursor through a 5-F catheter into a fusiform aneurysm model was feasible, leading to complete filling of the aneurysmal sac, which was visualized by fluoroscopy. The levels of occlusion by hydrogel precursors (1.8% and 2.1%) and calibrated microspheres (100–300 μm) in a rabbit renal model were compared. Embolization with hydrogel precursors was performed without clogging and the hydrogel achieved effective occlusion in more distal arteries than calibrated microspheres. In conclusion, this hydrogel possesses promising characteristics potentially beneficial for a wide range of vascular intervention procedures that involve embolization and drug delivery.     

Micromechanical properties of single crystal hydroxyapatite by nanoindentation

Knowledge of the intrinsic properties of hydroxyapatite (HAp) single crystals is important for the design of natural systems and will assist further improvements of manufactured biomaterials. Nanoindentation provides a useful tool for determining mechanical properties such as the hardness, elastic modulus and fracture toughness of small samples. A Berkovich indenter was placed on the side and basal planes of a natural single crystal of Durango HAp. The hardness and elastic modulus values obtained revealed higher values for the base (7.1 and 150.4 GPa) compared to the side (6.4 and 143.6 GPa). The cracking threshold, i.e., the load at which cracking initiates, revealed earlier crack formation on the base (at 8 mN) compared to the side (at 11 mN). Fracture toughness was measured as 0.45 ± 0.09 and 0.35 ± 0.06 MPa m^1/2 for the side and basal plane, respectively. These results suggest that crystals are less prone to cracking and resist microcrack events better on the side, which is useful in bone, while exposing the base, the hardest face, to minimize mass loss from abrasion with teeth.     

Polypeptide-based combination of paclitaxel and cisplatin for enhanced chemotherapy efficacy and reduced side-effects

A novel methoxy poly(ethylene glycol)-b-poly(l-glutamic acid)-b-poly(l-phenylalanine) (mPEG-b-P(Glu)-b-P(Phe)) triblock copolymer was prepared and explored as a micelle carrier for the co-delivery of paclitaxel (PTX) and cisplatin (cis-diamminedichlo-platinum, CDDP). PTX and CDDP were loaded inside the hydrophobic P(Phe) inner core and chelated to the middle P(Glu) shell, respectively, while mPEG provided the outer corona for prolonged circulation. An in vitro release profile of the PTX + CDDP-loaded micelles showed that the CDDP chelation cross-link prevented an initial burst release of PTX. The PTX + CDDP-loaded micelles exhibited a high synergism effect in the inhibition of A549 human lung cancer cell line proliferation over 72 h incubation. For the in vivo treatment of xenograft human lung tumor, the PTX + CDDP-loaded micelles displayed an obvious tumor inhibiting effect with a 83.1% tumor suppression rate (TSR%), which was significantly higher than that of a free drug combination or micelles with a single drug. In addition, more importantly, the enhanced anti-tumor efficacy of the PTX + CDDP-loaded micelles came with reduced side-effects. No obvious body weight loss occurred during the treatment of A549 tumor-bearing mice with the PTX + CDDP-loaded micelles. Thus, the polypeptide-based combination of PTX and CDDP may provide useful guidance for effective and safe cancer chemotherapy.     

Immunohistochemical localisation of renal cyclooxygenase-1 expression in non-steroidal anti-inflammatory drug-treated mice

The utility of cyclooxygenase-inhibiting non-steroidal anti-inflammatory drugs is limited by unwanted side effects that include disturbances in renal function. In order to further understand the mechanisms that underlie these renal side effects, the expression of the prostaglandin-synthesizing enzyme cyclooxygenase (COX) was examined by immunohistochemical methods in murine kidneys after treatment with indomethacin, a non-selective inhibitor or nimesulide, an inhibitor that preferentially and selectively blocks the COX-2 isoform of the enzyme. In untreated control kidneys, COX-1 protein was expressed in the glomeruli and parietal cells of the glomerular capsule, epithelial cells of the proximal and distal convoluted tubules including the juxtaglomerular region, and the collecting ducts. At therapeutic doses, indomethacin (10 mg/kg) did not alter renal COX-1 expression relative to immunoreactivity in untreated control kidney. By contrast, an equipotent therapeutic dose of nimesulide reduced renal COX-1 expression within the first 24 h of treatment. Taken together with the reports of reduced COX-1 expression prior to renal tissue damage following high-dose indomethacin treatment, our findings suggest that effects of NSAIDs on renal COX expression are dependent on dose and may be related to isoform specificity.     

TEGDMA-induced oxidative DNA damage and activation of ATM and MAP kinases

The development of strategies for the protection of oral tissues against the adverse effects of resin monomers is primarily based on the elucidation of underlying molecular mechanisms. The generation of reactive oxygen species beyond the capacity of a balanced redox regulation in cells is probably a cause of cell damage. This study was designed to investigate oxidative DNA damage, the activation of ATM, a reporter of DNA damage, and redox-sensitive signal transduction through mitogen-activated protein kinases (MAPKs) by the monomer triethylene glycol dimethacrylate (TEGDMA). TEGDMA concentrations as high as 3–5 mm decreased THP-1 cell viability after a 24 h and 48 h exposure, and levels of 8-oxoguanine (8-oxoG) increased about 3- to 5-fold. The cells were partially protected from toxicity in the presence of N-acetylcysteine (NAC). TEGDMA also induced a delay in the cell cycle. The number of THP-1 cells increased about 2-fold in G1 phase and 5-fold in G2 phase in cultures treated with 3–5 mm TEGDMA. ATM was activated in THP-1 cells by TEGDMA. Likewise, the amounts of phospho-p38 were increased about 3-fold by 3 mm TEGDMA compared to untreated controls after a 24 h and 48 h exposure period, and phospho-ERK1/2 was induced in a very similar way. The activation of both MAPKs was inhibited by NAC. Our findings suggest that the activation of various signal transduction pathways is related to oxidative stress caused by a resin monomer. Signaling through ATM indicates oxidative DNA damage and the activation of MAPK pathways indicates oxidative stress-induced regulation of cell survival and apoptosis.     

Symplocos cochinchinensis attenuates streptozotocin-diabetes induced pathophysiological alterations of liver,kidney, pancreas and eye lens in rats

The beneficial effects of hydroethanol extract of Symplocos cochinchinensis (SCE) has been explored against hyperglycemia associated secondary complications in streptozotocin induced diabetic rat model. The experimental groups consist of normal control (NC), diabetic control (DC), DC + metformin 100 mg kg⁻¹ bwd, DC + SCE 250 and DC + SCE 500. SCEs and metformin were administered daily for 21 days and sacrificed on day 22. Oral glucose tolerance test, plasma insulin, % HbA1c, urea, creatinine, aspartate aminotransferase, alanine aminotransferase, albumin, total protein etc. were analysed. Aldose reductase (AR) activity in the eye lens was also checked. On day 21, DC rats showed significantly abnormal glucose response, HOMA-IR, % HbA1c, decreased activity of antioxidant enzymes and GSH, elevated AR activity, hepatic and renal oxidative stress markers like malondialdehyde, protein carbonyls compared to NC. DC rats also exhibited increased level of plasma urea and creatinine. Treatment with SCE protected from the deleterious alterations of biochemical parameters in a dose dependent manner including histopathological alterations in pancreas. SCE 500 exhibited 46.28% of glucose lowering effect and decreased HOMA-IR (2.47), % HbA1c (6.61), lens AR activity (15.99%), and hepatic, renal oxidative stress and function markers compared to DC group. Considerable amount of liver and muscle glycogen was replenished by SCE treatment in diabetic animals. Although metformin showed better effect, the activity of SCE was very much comparable with this drug.     

Association of high HLA-E expression during acute cellular rejection and numbers of HLA class I leader peptide mismatches with reduced renal allograft survival

Non-classical Human Leukocyte Antigen (HLA)-E preferentially presents leader peptides derived from classical HLA-class I molecules. HLA-E can trigger opposed immune responses by interacting with inhibitory NKG2A or by activating NKG2C receptors on NK and T-cells. We studied the impact of HLA-E on renal allograft survival during acute cellular rejection. HLA-E expression was up-regulated in acute cellular rejection (ACR) biopsies (n = 12) compared to biopsies from 13 renal allografts with no rejection-signs. HLA-E up-regulation was correlated with numbers of HLA-class I leader peptide mismatches (p = 0.04). CD8+ and CD56+ infiltrating cells correlated with HLA-E expression (p < 0.0001 and p = 0.0009, respectively). Activating NKG2C receptor dominated on effector cells in biopsies and peripheral blood during ACR potentially allowing HLA-E-mediated immune activation. Moreover, HLA-E expression correlated with deterioration in renal allograft function (p < 0.008) and reduced allograft survival (p = 0.002). Our findings provide evidence that during renal allograft rejection HLA-E along with high numbers of mismatched HLA-class I leader peptides might represent additional targets for immune-activating responses.     

The use of biotinylated-EGF-modified gelatin nanoparticle carrier to enhance cisplatin accumulation in cancerous lungs via inhalation

To develop a polymer-anticancer drug conjugate, we employed gelatin nanoparticles (GPs) as carriers of cisplatin (CDDP) with anticipated improved therapeutic effect and reduced side effects. The anticancer activities of CDDP-incorporated in GPs (GP–Pt) with biotinylated-EGF (bEGF) modification (GP–Pt–bEGF) were studied. GP–Pt–bEGF with EGFR affinity produced much higher Pt concentrations in A549 cells (high EGFR expression) than in HFL1 cells (low EGFR expression). An in vitro anticancer study showed that GP–Pt–bEGF was more potent than free CDDP or GP–Pt because of its rapid effect on the cell cycle as well as a lower IC₅₀ (1.2 μg/ml) that inhibits A549 cell growth. PI staining showed that cells treated with GP–Pt-bEGF for only 4 h had the highest sub-G1 population.The CDDP formulations – free CDDP, GP–Pt, and GP–Pt–bEGF – were given by intratumorous injections to SCID mice in a subcutaneous model. This treatment showed that GP–Pt–bEGF had stronger anti-tumor activity and was less toxic than free CDDP in vivo. Mice treated with GP–Pt–bEGF showed slight body weight loss, whereas free CDDP treatment at the same dose caused a body weight loss of 20–30%. Furthermore, these formulations were given to mice with lung cancer via aerosol delivery. This treatment showed that inhaled GP–Pt–bEGF could target EGFR-overexpressing cells to achieve high cisplatin dosage in cancerous lungs.To summarize, gelatin nanoparticles loaded with CDDP and decorated with EGF tumor-specific ligand were successfully developed. Their in vitro and in vivo targeting ability and anticancer effect were confirmed. The aerosol delivery of the nanodrug carrier was demonstrated. Simple aerosol delivery of targeted drug carriers may prove useful for the clinical treatment of lung cancer patients.     

Nonlinear properties of cardiac rhythm and respiratory signal under paced breathing in young and middle-aged healthy subjects

We examined the effects of gender and age in young and middle-aged subjects on the level of cardio-respiratory interaction by analyzing properties of cardiac, respiratory and cardiac-respiratory regulatory mechanisms under paced breathing. In 56 healthy subjects, ECG (RR interval) and respiratory signal were simultaneously acquired in supine position at paced (0.1–0.45 Hz, steps of 0.05 Hz) and spontaneous breathing. The participants were divided into gender matched group of young adults (19–25 years old) and middle-aged adults (35–44 years old). Power spectral analysis was applied on RR interval time series and spectral components in very low frequency (VLF), low frequency (LF) and high frequency (HF) ranges were computed. We also calculated sample entropy of RR interval series (SampEnRR), respiratory series (SampEnResp), and their cross-sample entropy (cross-SampEn). Under paced breathing, reduction of all spectral powers with age (p < 0.05) is not gender dependent but reduction of some entropy measures is; SampEnRR and SampEnResp were lower only in men (p < 0.05). In the middle-aged subjects, effect of gender on spectral measures is significant; males had lower HF (p < 0.05). Pattern of dependencies of SampEn and cross-SampEn on paced breathing frequency were significantly different in men (young vs. middle-aged, p = 0.001 and p = 0.037) and in middle-aged subjects (females vs. males, p = 0.011 and p = 0.008). In middle-aged males, lower entropy measures indicated reduced and less complex partial cardiac and respiratory control, and central cardio-respiratory control. In conclusion, in healthy middle-aged subjects changes in cardio-respiratory coupling are detectable only in males.     

Association of FCGR2A p.R131H and CCL2 c.-2518 A > G gene variants with thrombocytopenia in patients with dengue virus infection

FCGR2A and CCL2 gene variants are important in dengue pathogenesis and were investigated in 122 dengue patients (DENs) [89 dengue fever (DF) and 33 dengue hemorrhagic fever (DHF)] and 107 healthy controls (HCs) to find out their association with severity of dengue. Genotype frequencies of FCGR2A p.R131H and CCL2 c.-2518 A > G polymorphisms were not different between DF, DHF and HC. Significantly higher frequency of R/R genotype of FCGR2A p.R131H was observed in DEN cases with thrombocytopenia (TP) while the G/G genotype of CCL2 c.-2518 A > G was observed only in DEN cases with TP (p < 0.005). These results suggest that FCGR2A and CCL2 gene variants were associated with the risk of TP in dengue infections.     

Transient disruption of liver gap junctional intercellular communication and induction of apoptosis after administration of 1,4-bis[2-(3,5 dichloropyridyloxy)]benzene in mice

Gap junctional intercellular communication (GJIC) and connexin expression (Cx26 and Cx32) in mouse liver were studied after administration of 4-bis[2-(3,5 dichloropyridyloxy)]benzene (TCPOBOP), a phenobarbital-like enzyme inducer. Female C57Bl/6 mice were administered TCPOBOP (5.8 mg/kg BW) and euthanized 0, 24, 48 and 72 hours later. Liver samples were snap frozen, or fixed in formalin, or submitted to GJIC analysis. The proliferating cell nuclear antigen (PCNA) immunohistochemistry and the Western blotting for Cx26 and Cx32 were performed. After 48 and 72 h of drug administration the liver-to-body weight ratio was increased 70% and 117% (p<0.0001), respectively. There were temporal-dependent alterations in liver histopathology and a significant increase in cell proliferation was noted after 48 h and sustained after 72 h, though to a lesser extent (p<0.0001). In addition, TCPOBOP administration induced apoptosis, which appeared to be time-dependent showing statistical significance only after 72 h (p<0.0001). Interestingly, a transient disruption by nearly 50% of GJIC capacity was detected after 48 h of drug ingestion, which recovered after 72 h (p=0.003). These GJIC changes were due to altered levels of Cx26 and Cx32 in the livers of TCPOBOP-treated mice. We concluded that a single administration of TCPOBOP transiently disrupted the levels of GJIC due to decreased expression of connexins and increased apoptotic cell death in mouse liver.     

Poly(amidoamine) dendrimer–drug conjugates with disulfide linkages for intracellular drug delivery

Understanding and improving drug release kinetics from dendrimer–drug conjugates are key steps to improve their in vivo efficacy. N-Acetyl cysteine (NAC) is an anti-inflammatory agent with significant potential for clinical use in the treatment of neuroinflammation, stroke and cerebral palsy. There is a need for delivery of NAC which can enhance its efficacy, reduce dosage and prevent it from binding plasma proteins. For this purpose, a poly(amidoamine) dendrimer–NAC conjugate that contains a disulfide linkage was synthesized and evaluated for its release kinetics in the presence of glutathione (GSH), cysteine (Cys), and bovine serum albumin (BSA) at both physiological and lysosomal pH. The results indicate that the prepared conjugate can deliver ～60% of its NAC payload within 1 h at intracellular GSH concentrations at physiological pH, whereas the conjugate did not release any drug at plasma GSH levels. The stability of the conjugate in the presence of bovine serum albumin at plasma concentrations was also demonstrated. The efficacy of the dendrimer–NAC conjugate was measured in activated microglial cells (target cells in vivo) using the reactive oxygen species (ROS) assay. The conjugates showed an order of magnitude increase in antioxidant activity compared to free drug. When combined with intrinsic and ligand-based targeting with dendrimers, these types of GSH sensitive nanodevices can lead to improved drug release profiles and in vivo efficacy.     

Syndrome de basse T3 chez des patients âgés présentant une dénutrition modérée ou sévère

Under nutrition causes alterations in serum thyroid function tests referred as “non-thyroidal illness syndrome” (NTIS). We determined serum thyroid hormones in elderly patients (≥ 70 years) with mild (25 ≤ albuminemia < 35 g/l, N = 64) or severe (albuminemia < 25 g/l, N = 67) under nutrition, compared to well-nourished patients (albuminemia ≥ 35 g/l, N = 78). Patients with under nutrition had lower (32%) free T3 (FT3) and higher (21%) free T4 (FT4) concentrations than in controls. TSH level was similar in the three groups of patients. Therefore, malnourished elderly patients showed euthyroidism profile, whatever the severity of under nutrition. The decrease in FT3 level was more marked in patients with severe under nutrition. In addition, there was a positive correlation between FT3 and albumin, transthyretin and transferrin and a negative correlation with PINI (“prognostic inflammatory and nutritional index”). These data showed that FT3 is a good marker of severity of under nutrition in elderly patients.     

Hepatic metabolism of ibuprofen in rats under acute hypobaric hypoxia

Hypobaric hypoxia induced at high altitude causes a subnormal oxygen concentration in cells which affects the drug metabolic and pharmacokinetic (PK) capacity of the body. The metabolism and PK of drugs like ibuprofen may be impaired under hypoxia and may require a different than usual therapeutic dose regimen to ensure safe therapy. The present investigation was undertaken to evaluate the effect of acute hypobaric hypoxia (AHH) on hepatic metabolism and PK of ibuprofen in rats. Animals were exposed to simulated altitude of 7620 m (～25,000 ft) for AHH exposure (6 and 24 h) in a decompression chamber and were administrated with single dose of ibuprofen (80 mg/kg body weight, p.o.). The results showed that GST activity was significantly reduced at 6 h (15%) and 24 h (23%) (p < 0.05) in hypoxic group as compared to normoxic. A significant increase by 20–24% (p < 0.05) in AST level was observed after AHH exposure. LDH activity also exhibited significant increase (p < 0.05) after 24 h of AHH. A significant down-regulated CYP2C9 level and mild histopathological changes were observed after 24 h of AHH. Furthermore, PK variables viz. elimination half-life (T½) and mean residence time (MRT) of ibuprofen exhibited significant increase by 42% and 51% (p < 0.05) respectively after 24 h of AHH. Thus, results suggest that AHH exposure of 24 h significantly affects phase II conjugation pathway, CYP2C9 level, AST level, liver histology and PK parameters. This asserts that AHH can impair disposition of ibuprofen however, it requires further investigation under chronic hypobaric hypoxic conditions.     

Efficacy and safety of single-dose local infiltration of analgesia in total knee arthroplasty: A meta-analysis of randomized controlled trials

PurposeTo examine the efficacy and safety of single-dose local infiltration of analgesia (LIA) for post-operative pain relief in total knee arthroplasty (TKA) patients.MethodsA systematic electronic literature search (up to Aug 2013) was conducted to identify the RCTs that address the efficacy and safety of single-dose LIA in the pain management after TKA. Subgroup analysis was conducted to determine changes of visual analog score (VAS) values at six different postoperative time points. Weighted mean differences or relative risks with accompanying 95% confidence intervals were calculated and pooled using a random effect model.ResultsEighteen trials involving 1858 TKA patients met the inclusion criteria. The trials were liable to medium risk of bias. The VAS values at postoperative 2 h, 4 h, 6 h, 12 h, 24 h, and 48 h per patient were significantly lower in the LIA group than in the placebo group, and the former group also had less morphine consumption and better early functional recovery including range of motion, time to straight leg raise and 90° knee flexion than the latter group. No significant difference in length of hospital stay or side effects was detected between the two groups.ConclusionsThe current evidence shows that the use of single-dose LIA is effective for postoperative pain management in TKA patients, with satisfactory short-term safety. More high-quality RCTs with long-term follow-ups are required for examining the long-term safety of single-dose LIA.Level of evidenceI, II     

Novel iron–polysaccharide multilayered microcapsules for controlled insulin release

Iron–polysaccharide complexes have been extensively used for the treatment of iron-deficiency anemia without side-effects. In this study, insulin-loaded microcapsules were prepared via layer-by-layer deposition of oppositely charged Fe³⁺ and dextran sulfate (DS) onto the surface of insulin microparticles. Fe³⁺ was combined with DS via both electrostatic interaction and chemical complexation process, leading to the formation of a stable complex of Fe³⁺/DS. Subsequently, protamine was used as the outermost layer of the insulin-loaded microcapsules to facilitate nuclear delivery. The sufficient charge reversal with successive deposition cycles and successful fabrication of hollow microcapsules provided strong evidence for the growth of (Fe³⁺/DS)_n multilayer on the surface of microparticles. The experiments showed that the microcapsules successfully entrapped insulin with encapsulation efficiency of 70.56 ± 0.97% and drug loading content of 46.15 ± 0.97%. It was found that the release time and hypoglycemic effect increased as the number of deposited bilayers increased. The insulin-loaded microcapsules significantly improved glucose tolerance from 2 h (free insulin) to even 12 h (insulin-loaded microcapsules with 10 bilayers). Moreover, the microcapsules with protamine as the outermost layer displayed a prolonged and stable glucose-lowering profile over a period of over 6 h compared with Fe³⁺ as the outermost layer. These findings indicate that such microcapsules can be a promising approach for the construction of an effective controlled release delivery system of insulin as well as other proteins with short half-life time.